Acquired immunity is like a smart shield for the human body. When germs attack, the body fights back. But it also learns from the fight. It remembers the bad germs so they cannot hurt us again. This keeps people healthy for a long time. It is why vaccines work so well. It is a special defense that grows stronger as we grow up. Without it, we would get sick very often. It protects us from many dangerous diseases. The following essays are written for students from Class 1 to Class 12.
Essay on Acquired Immunity in 100 Words
Acquired immunity is a special protection. It is not something we are born with. The body gets it over time. When a germ enters, the body learns how to kill it. It makes special tools called antibodies.
Next time the same germ comes, the body remembers. It attacks fast. This is why we usually get chickenpox only once. Vaccines also give this immunity. They teach the body without making us sick. It is a smart way to stay safe. It helps us live a long and healthy life. It is our body’s best defense system.
Essay on Acquired Immunity in 150 Words
Acquired immunity is also known as adaptive immunity. It is a defense that the body builds during life. It is different from the protection we are born with. The body learns to recognize bad germs.
There are two main ways to get it. One is by getting sick. If a person gets a virus, the body fights it off. It keeps a memory of that fight. The second way is through shots or vaccines. A vaccine shows the body what the germ looks like.
The body then prepares special soldiers to fight. These are called antibodies. They stay in the blood for a long time. If the real germ attacks later, the soldiers are ready. This system makes the immune system very strong. It adapts to new threats. It keeps children and adults safe from many illnesses every day.
Essay on Acquired Immunity in 200 Words
Acquired immunity is how the body learns to defend itself. Think of the immune system as an army. When a new enemy attacks, the army studies it. It makes specific weapons to defeat that specific enemy. These weapons are proteins called antibodies.
This type of immunity is not present at birth. It develops as we grow. When a child plays outside, they meet new germs. The body practices fighting them. This makes the child stronger. This is called active immunity.
Sometimes, the body gets help. A mother passes protection to her baby through milk. This is called passive immunity. It lasts for a short time. Active immunity lasts for a long time, often for life.
Vaccines are a great invention. They use this system to save lives. They introduce a weak germ to the body. The body practices fighting it safely. Later, if the strong germ comes, the body wins easily. This prevents terrible diseases like polio and measles. It is a miracle of nature. It turns our body into a fortress. It ensures we can play and work without fear of getting sick.
Essay on Acquired Immunity in 250 Words
Acquired immunity is the body’s smart way of fighting disease. It is specific to each germ. The body has a memory. It remembers every germ it has ever defeated. This is why we rarely get the same cold twice in a row.
There are two main players in this system. These are the B cells and T cells. They are white blood cells. B cells are like archers. They shoot antibodies at the germs. T cells are like soldiers. They fight the germs up close. They work together to clear the sickness.
There are two types of acquired immunity: active and passive. Active immunity happens when our own body does the work. This happens after an infection or a vaccine. It takes time to build, but it lasts a long time.
Passive immunity is borrowed protection. A baby gets it from the mother before birth. It can also come from medicine. This protection is instant but does not last long. It fades away after a few months.
Vaccination is the most common way to build acquired immunity today. Doctors give a shot to teach the immune system. It is like a fire drill. The body learns the escape route before the fire starts. This prepares the body for real danger. Because of this, many deadly diseases are now gone. It is vital for public health. It keeps communities safe and strong.
Essay on Acquired Immunity in 300 Words
Acquired immunity is a powerful shield that develops throughout our lives. It is not innate. This means we are not born with it. We earn it by exposing our bodies to the world. It is highly specific. This means it targets one specific germ at a time.
The immune system identifies foreign invaders. These are called antigens. When the body spots an antigen, it sounds an alarm. It produces antibodies to lock onto the invader. Once the invader is marked, other cells destroy it.
One amazing feature is immunological memory. After the battle is won, some cells stay behind. These are memory cells. They sleep in the body for years. If the same germ returns, they wake up instantly. They produce a massive attack very quickly. The germ is killed before we even feel sick.
There is active acquired immunity. This is when the body makes its own antibodies. Getting the flu gives you this. Getting a flu shot also gives you this. It is long-lasting protection.
Then there is passive acquired immunity. This is temporary. Newborn babies have this. They get antibodies from their mother. This protects them while their own system is weak. People can also get injections of antibodies for snake bites. This saves lives quickly but does not last.
This system is why hygiene and vaccines are important. We must keep our bodies strong so they can learn. Eating healthy food helps the immune system build these cells. Without acquired immunity, humans would not survive long. We face millions of germs every day. This system is our silent guardian. It works day and night to keep us alive and well.
Essay on Acquired Immunity in 500 Words
Acquired immunity is the second line of defense in the human body. The first line is the skin and saliva. When germs get past the skin, acquired immunity takes over. It is a complex system that learns and remembers. It is also called adaptive immunity because it adapts to new germs.
The process starts when a germ enters the body. The germ carries a marker on it. This marker is called an antigen. The immune system sees this antigen and knows it is bad. It calls for help. Special white blood cells come to the rescue.
There are two main types of cells involved. These are B lymphocytes and T lymphocytes. We call them B cells and T cells. B cells are the weapon factories. They produce proteins called antibodies. These antibodies travel in the blood. They stick to the germs and stop them from moving.
T cells are the fighters. Some T cells help the B cells work better. Other T cells attack the infected cells directly. They destroy the cells where the virus is hiding. This stops the virus from spreading.
After the fight is over, most of these cells die. But a few remain. These are the memory cells. They are like the history books of the body. They remember the face of the enemy. If the same enemy comes back years later, the memory cells act fast. They create a new army in hours. This is why we are immune to diseases we have had before.
Immunity can be natural or artificial. Natural immunity happens by chance. You catch a cold, you get better, and you are immune. Artificial immunity happens by choice. This is vaccination. A vaccine puts a dead or weak germ into the body. The body attacks it and builds memory. It is a very safe way to learn without suffering.
Passive immunity is another type. This is when you get antibodies from someone else. A baby gets them from the mother. This protects the baby for the first few months. Sometimes, doctors give antibodies to treat rare poisons. This works fast but wears off quickly.
Acquired immunity is vital for survival. Without it, a simple infection could be fatal. It allows us to live in a world full of bacteria and viruses. It allows us to travel and meet people safely.
However, sometimes the system makes a mistake. It might attack the body’s own cells. This is called an autoimmune disease. Or it might overreact to dust or pollen. This is called an allergy. But most of the time, it works perfectly.
To keep this system strong, we need to take care of ourselves. Good sleep and healthy food are fuel for immunity. Exercise also helps the blood move cells around. Acquired immunity is a gift of nature. It protects our past, present, and future health.
Essay on Acquired Immunity in 1000 Words
Acquired immunity, also known as adaptive immunity, is a remarkable defense mechanism. It is a specific immune response. This means it targets specific invaders. Unlike innate immunity, which we are born with, acquired immunity develops over time. It is a learned response. As we grow and interact with our environment, our body builds a library of defenses. This system is what allows humans to survive in a world filled with pathogens. It is complex, intelligent, and highly effective.
How the System Works
The process begins when a pathogen enters the body. A pathogen is a germ like a virus or bacteria. The immune system detects it. It recognizes the germ as foreign because of antigens. Antigens are like the flags of the enemy. The body reads these flags and sounds the alarm.
The response involves two major types of white blood cells. These are B cells and T cells. They are the special forces of the body. Each B cell and T cell is designed to fight one specific antigen. When they find their match, they become active. They begin to multiply rapidly. This is why lymph nodes often swell when we are sick. They are busy making an army of cells.
Humoral Immunity
One part of acquired immunity is called humoral immunity. This is controlled by B cells. B cells do not enter the fight directly. Instead, they produce antibodies. Antibodies are Y-shaped proteins. They circulate in the blood and lymph fluid.
When an antibody finds an antigen, it attaches to it. This marks the germ for destruction. It can also neutralize the germ. This means the germ cannot enter healthy cells. Antibodies are very specific. An antibody for the flu will not work on the measles. This specificity is the key to acquired immunity. It ensures the right weapon is used for the right enemy.
Cell-Mediated Immunity
The other part is cell-mediated immunity. This involves T cells. T cells are crucial for fighting viruses that hide inside cells. B cells cannot reach inside a cell. But T cells can.
There are Helper T cells and Killer T cells. Helper T cells manage the battle. They send signals to B cells and other immune cells. They tell them to work harder. Killer T cells are the executioners. They find infected body cells and destroy them. This stops the infection from spreading to new cells. It is a harsh but necessary action to save the body.
The Power of Memory
The most amazing feature of acquired immunity is memory. After the infection is cleared, the army of cells dies off. However, a few cells remain behind. These are called memory B and T cells. They can live for decades.
These memory cells patrol the body. They are always watching. If the same pathogen tries to invade again, they react instantly. They produce a massive amount of antibodies very quickly. The pathogen is destroyed before it can cause any harm. The person usually does not even feel sick. This is why we rarely get diseases like mumps more than once. The body remembers and wins the fight immediately.
Active Immunity
Acquired immunity can be divided into two categories: active and passive. Active immunity is when your own body does the work. It produces its own antibodies and memory cells.
There are two ways to get active immunity. The first is natural active immunity. This happens when you get an infection. You get sick, you fight it, and you recover. The second is artificial active immunity. This comes from vaccination. A vaccine contains a harmless part of a germ. It tricks the body into thinking it is under attack. The body builds defenses without the risk of severe illness. This is the safest way to build immunity.
Passive Immunity
Passive immunity is different. It is borrowed protection. The body does not make the antibodies itself. It receives them from an outside source.
Natural passive immunity happens between a mother and child. Antibodies pass through the placenta to the baby. They also pass through breast milk. This protects the infant while their own immune system is developing. Artificial passive immunity involves medicine. Doctors can inject antibodies into a patient. This is used for snake bites or rabies. It provides immediate protection. However, it is temporary. Since the body did not make the cells, there is no memory. The protection fades in a few weeks or months.
Vaccination and Public Health
Vaccines are the greatest tool of acquired immunity. By using this natural system, scientists have eradicated diseases. Smallpox is gone because of vaccines. Polio is almost gone. Herd immunity occurs when most people are immune. This protects those who cannot get vaccines, like sick babies.
It is important to keep vaccinations up to date. Some vaccines need boosters. Tetanus shots are needed every ten years. This reminds the memory cells of their job. It keeps the defense strong.
When the System Fails
Sometimes, acquired immunity makes mistakes. It can attack harmless things like pollen or peanuts. This causes allergies. In more serious cases, it attacks the body’s own tissues. This leads to autoimmune diseases like Type 1 diabetes. In these cases, the immune system is too active. Doctors must give medicine to calm it down.
Conclusion
Acquired immunity is a complex and vital system. It adapts, learns, and remembers. It turns every illness into a lesson. It creates a personal shield for each individual based on their life experiences. Without it, humans would be vulnerable to every germ in the air. It is a masterpiece of biology. By understanding it, we can make better choices for our health. We can appreciate the silent war our body fights and wins every day. It is the ultimate guardian of our health and lives.
FAQ
What is acquired immunity?
Acquired immunity is protection that your body learns over time. You are not born with it. You get it after being sick or getting a vaccine. It helps your body remember germs and fight them off faster next time.
How long does acquired immunity last?
It can last for a very long time, sometimes for your whole life. Active immunity, like from vaccines, lasts the longest. Passive immunity, like from a mother to a baby, only lasts a few months.
What are B cells and T cells?
B cells and T cells are special helpers in your blood. B cells make antibodies that stick to germs. T cells fight germs that hide inside your body cells. They work together to keep you safe.
Why do we need vaccines?
Vaccines teach your body how to fight bad germs without you getting sick. They show your immune system what the enemy looks like. This helps your body build a strong defense for the future.
